Chassis, converted for a battery electric vehicle

This application is a § 371 National Phase Application of International Application No. PCT/US2022/027844, filed on May 5, 2022, now International Publication No. WO 2022/235913, published on Nov. 10, 2022, which International Application claims the benefit under 35 USC 119(e) of U.S. Provisional Application No. 63/184,343, filed on May 5, 2021, and claims priority to Belgian Patent Application No. BE 2021/0050, filed on Jul. 22, 2021, all of which are incorporated herein by reference in their entirety.

The present invention relates to a chassis for a vehicle, converted such that it can be used for a battery electric vehicle. More in particular the invention relates to such chassis and the corresponding method for converting the chassis of a vehicle, in particular a truck, powered by a combustion engine, to a vehicle, in particular a truck, powered by an electromotor. Still more in particular, the invention relates to a method whereby a part of the chassis of the truck is retained and is joined to a new chassis part by means of a merger module.

The invention also relates to a chassis manufactured according to this method, as well as to a vehicle powered by an electromotor, comprising such chassis.

Differently phrased, the invention relates to a dual function merger module for two different chassis frames for the conversion of an Internal Combustion Engine (ICE) chassis frame to a Battery Electric Vehicle (BEV) chassis frame. Said application would occur when two chassis frames with different widths need to be joined together for the purpose of converting ICE vehicles to BEV's to facilitate modular assembly. The merger module facilitates the difference in size as well integrates an electric motor drive solution for said conversion.

It is common practice in the commercial vehicle industry to build a vehicle chassis consisting of a frame structure with two opposing side rails or longitudinal frame rails running along the length of the vehicle. Said longitudinals are usually L or C shaped and may get doubled up to increase strength and load bearing capacity. These longitudinal frame rails are joined together by at least one or more connecting members, known as crossmembers. Within this industry, it is a recognized practice to utilize cross members that are located on the inside of the chassis frame, i.e. they have cross members with 2 outer surfaces that join up to the inner surfaces of the frame rails to make up the body of the chassis frame structure. Such cross members are designed to stiffen the frame. Traditional types of crossmembers eliminate the possibility of component installation between the chassis rails from the forward-facing or rear-facing ends of the chassis frames, and instead, need to be accessed from the upper or lower direction.

For battery electric and other alternative drive commercial vehicles it is of key importance to develop such frame structure so to maximize the available space between the longitudinal frame rails in order to increase battery packaging density. Only in this manner maximum battery capacity can be reached.

In converting ICE vehicles to BEV's, modifications to the existing chassis structure may be required. After such conversion, the chassis structure comprises a front section and a rear section, in which the rear section is a part of the original ICE chassis structure and the front section is a new chassis structure to accommodate the BEV powertrain more optimally.

The terms front and rear section should be understood as being the front and rear section of the chassis, viewed in the driving direction of the vehicle.

It is the goal of the invention to find an optimized way of mounting these two chassis frames together with improved results in ergonomics, less material and component waste, shorter assembly lead-times, less assembly costs and provide improved robustness and torque strength to support a central electric motor installation. The way such frames are joined and its location will make a great deal of difference in overall chassis strength and level of complexity of operation. The location and mounting of the electric drive motor is of particular importance for a battery electric vehicle as it will cause high torques on the frame, exceeding the one caused by the traditional diesel driveline.

The present invention relates to a chassis design and a method for manufacturing such chassis, for such a converted new vehicle that allows the assembly of a wider frame to be connected to a cut-off chassis frame of an existing commercial vehicle, providing for a less complex and improved way of recuperating components of the original vehicle.

The goal of the present invention is to offer a solution to the abovementioned and related drawbacks, as a method along claimis offered.

To that end, the present invention relates to a method for converting an ICE chassis frame to a BEV chassis frame, comprising the following steps:

According to a preferred embodiment of the method of the invention, the steps d and e are performed after execution of the steps a, b and c.

According to a further preferred embodiment of the invention, the method comprises the additional step that the batteries for the electric power train are placed in the space formed between the longitudinals () of the new chassis-part ().

The invention also relates to a chassis, manufactured according to the methods abovementioned.

The invention also relates to a battery powered vehicle, comprising the chassis manufactured according to the method of the invention.

More in particular the invention relates to the method(s), the chassis and the vehicle as set forth in the appended claims.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well as the singular forms, unless the context clearly indicated otherwise. It will be further understood that the terms “comprises” and or “comprising,” when used in this specification, specify the presence of stated features, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and/or groups thereof.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one having ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

In describing the invention, it will be understood that a number of techniques and steps are disclosed. Each of these has individual benefit and each can also be used in conjunction with one or more, or in some cases all, of the other disclosed techniques. Accordingly, for the sake of clarity, this description will refrain from repeating every possible combination of the individual steps in an unnecessary fashion. Nevertheless, the specification and claims should be read with the understanding that such combinations are entirely within the scope of the invention and the claims.

A chassis frame comprising of a plurality of one or more U-shaped cross members and two longitudinal frame rails, is discussed herein. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be evident, however, to one skilled in the art that the present invention may be practiced without these specific details.

The present disclosure is to be considered as an exemplification of the invention and is not intended to limit the invention to the specific embodiments illustrated by the figures or descriptions below.

In order to further illustrate the invention, hereinafter some preferred embodiments are described of the method for the manufacturing of a converted chassis according to the invention.

The present invention relates to a method for the manufacturing of a converted chassis for a battery electric powered vehicle.

The invention also relates to a merger module that enables two different chassis parts to be joined to one integrated chassis for a battery electric powered vehicle.

This integrated chassis comprises two parts:

The rear part of the chassis of the original vehicle comprises the rear axle(s) and suspension of this vehicle and is completely recycled or re-used as this original chassis part is cut-off before the rear axle(s) and suspension.

The term “rear part” hereby relates to the rear part of the chassis of the original vehicle, seen in the driving direction of the vehicle.

The second part, namely the new chassis, comprises two longitudinal rails, hereinafter referred to as longitudinals, running in the longitudinal direction of the vehicle, at either side.

These longitudinals are connected to each other by connecting members, cross-wise positioned, hereinafter referred to as cross-members.

As set forth above, the BEV chassis frame comprises off the rear part of the ICE chassis frame, and a new front chassis frame. The rear part of the ICE chassis frame includes the axle and suspension mounting of the original ICE vehicle, and will be fully recuperated from the original vehicle by means of cutting-off the old chassis frame in front of the rear axle and suspension mounting. The new front chassis frame consists of 2 lateral frame rails running in the longitudinal direction of the vehicle, separated by cross members to maximize the inner space to increase storage and installation of battery packs up to the beginning of the rear section. Said spacing is wider than the original ICE chassis frame. On these lateral frame rails, a new front axle and suspension gets mounted in combination with any other hardware and subassemblies related to the design of the BEV powertrain design. Said BEV chassis frame is designed to achieve a cost-effective solution to recuperate as much as possible of the original ICE chassis frame, while creating the inner front chassis frame space needed for an enhanced and maximized battery storage preferred for a BEV chassis frame.

In embodiments of the invention, the mounting process to the new frame can be categorized as new practices in the industry consisting of two procedures; preparation work and final assembly. Whereas the preparation work consists of both the pre-assembly of the new front chassis frame and the cut-off of the original ICE chassis frame, the final assembly work consists of a cost effective, self-positioning mounting of the original ICE chassis frame into the pre-assembled new frame to form the BEV chassis frame.

Once merged, both frames are joined together through the use of fasteners such as bolts and nuts, running through a merger module. The location at which point these two frames are fastened together is referred to as the “Merger Point”.

In embodiments of the invention, the merger point will be the location of the mounting of the central electric motor drive. The mounting brackets of the electric motor drive will be integrated into the pre-assembly of the merger module, and therefore will be designed in a way it allows for the mechanical support of the motor drive, potentially its power electronics while providing high torsion strength to the original rear end of the ICE chassis frame, and reducing stress on the new front chassis frame.

In embodiments of the invention, the merger module, possibly consisting of several brackets, can be pre-assembled onto the rear end of the original ICE chassis frame, which allows for the front connection of a pre-assembly of a new front chassis frame. This subassembly allows for the difference in frame width and for easy of assembly to form fit the actual merger point, providing tight tolerance matching and secure a stable connection of the 2 frames to each other. Said merger module will be designed in a way it allows for self-positioning or form-lock of the rear ICE chassis frame and the new front chassis frame to create the BEV chassis frame.

In embodiments of the invention, the mounting of the two chassis frames as well as the mounting of the electric motor, through the means of combined fasteners allows for a more ergonomic, quality secured and cost-effective assembly operation. The advantage of this design is that modular assembly is facilitated.

In these figures use has been made of the following reference signs:

The present invention will now be described by referencing the appended figures representing preferred embodiments.shows the side view connection of the BEV chassis frame, consisting of the rear end of the cut-off ICE vehicle chassis frameattached to a front section of the new longitudinal frame railswhich are connected by respective crossmembers. At the Merger Point, the section where the two longitudinal frame rails are connected to the rear end of the ICE chassis frame, the electric drive unit or electromotoris mounted to the dual function merger module, as to provide optimal strength and transfer of torque to the original ICE chassis frameand to avoid exerting torsion on the front longitudinal frame rails.

Referring now to, in an advantageous embodiment of the invention, the top plan view shows how the dual function merger module allows the rear end of the cut-off ICE chassis frameto attach to the front section of the wider longitudinal frame railsto increase the available space between the chassis rails for battery electric driveline components such as batteries and power electronics. The assembly of the rear end of the ICE chassis frameand the wider longitudinal frame railsmake up the BEV chassis frame. The connection is achieved by creating the merger module in such a way, through a plurality of brackets, that these chassis frames with different widths can be assembled while incorporating the mounting of the electric drive unit.

Referring now toshowing a cross section of a potential merger module, consisting of a longitudinalin the forward facing direction of the rear end of the cut-off CE chassis frame, the longitudinalof the new front chassis frameand the plurality of bracketsneeded to bridge the distance between both chassis frames. The plurality of brackets of the dual function merger moduleare attached to the motor mounting platefor the electric motor. All these components are mounted together by a series of shared fastenersThere are many different engineering solutions to create the correct spacing distance for the dual function merger moduleand their attachment to the motor mounting plate. Inthe spacers are consisting of tubes welded to the motor mounting bracket.

Another advantageous embodiment of the invention is the form fit of the actual merger point for improved ergonomics, providing tight tolerance matching and secure a stable connection of the 2 frames to each other. Both frame rails of the front longitudinaland the longitudinal of the cut-off ICE chassis framehave a U shape, where the rails are oriented in such a way that the flanges are running on the top and bottom in the forward facing direction. Referring to, it is possible to see that the inner surface of the upper flange of the front longitudinalis touching the outer surface of the upper flange of the longitudinalfrom the cut-off ICE chassis frame. The merger module will be designed in a way it allows for self-positioning or form-lock of the rear ICE chassis frame and the new front chassis frame to create the BEV chassis frame.

Another advantageous embodiment of the invention, referring to, showing a cross section of a subassembly of the dual function merger module, is the improved ergonomics for installation of the new front chassis frame, to the rear cut-off ICE chassis frame, by allowing subassembly. Given the pre-assembly of the merger modulemade up of the motor mounting plateand the plurality of brackets, to the cut-off ICE chassis frame, the new front longitudinal frame rails. Can be slid over the pre-assembly, after which both frames are fastened together, forming the new BEV chassis frame.